The Seasonic Prime 850W is one of the first power supplies for end customers featuring 80 Plus Titanium efficiency levels already well below the 1kW mark. This unit is based on a further improved platform, when compared to the Seasonic Platinum Series, which allows to comply with Titanium efficiency standards.
On the following pages we will have a close look at the Seasonic Prime Titanium 850W power supply and show you what it can do.
| Page 1 - Introduction |
| Page 2 - Preview |
| Page 3 - Delivery / Specs |
| Page 4 - A Look Inside |
| Page 5 - Result Analysis and Discussion |
| Page 6 - Conclusion |
Preview
| Page 1 - Introduction |
| Page 2 - Preview |
| Page 3 - Delivery / Specs |
| Page 4 - A Look Inside |
| Page 5 - Result Analysis and Discussion |
| Page 6 - Conclusion |
Delivery and Specifications
Delivery |
|
| Cable | Length |
| 1 x ATX 20+4 pin | 61 cm |
| 2 x EPS/ATX 12V 8 & 4+4 pin | 66 cm |
| 4 x PCI-E 6+2 pin | 75 cm |
| 1 x 2 SATA | 35, 46.5 cm |
| 2 x 4 SATA | 45, 46.5, 58, 69.5 cm |
| 1 x 2 Molex | 35, 46.5 cm |
| 1 x 3 Molex | 45, 57, 69 cm |
| 1 x 5.25 to 3.5 | 11 cm |
The delivery of the Prime Titanium 850W is very good. Considering the wattage we like that there are four PCIe cables with a single connector. Apart from that up to 10 devices with SATA power plug as well as 5 devices with Molex connectors can be provided with power.
With this power supply Seasonic is offering a single rail design regarding 12V. In total you get 70A, which can be turned into heat by the graphics cards for instance.
Specifications (according to Seasonic) |
|||
| Voltage | Current | Power | |
| + 3.3 V | 20 A | 100 Watt | 850 Watt (Total) |
| + 5.0 V | 20 A | ||
| + 12 V | 70 A | 840 Watt | |
| - 12 V | 0.3 A | 3.6 Watt | |
| + 5 Vsb | 3.0 A | 15 Watt | |
The Prime Titanium 850W has been 80Plus Titanium certified. This means, that the efficiency of this PSU should be above 90% at 10% load, 92% at 20% load, above 94% at 50% load and above 90% at 100% load.
At this point the feature list:
- 80Plus Titanium
- OVP, UVP, OCP, SCP, OPP, OTP
- Dimensions (W x H x D): 150 mm x 86 mm x 170 mm
- 135 millimeter fan
- Passive while below 50% load
- Warranty: 7 Years
- Price: 209 CHF / 251 Euro
| Page 1 - Introduction |
| Page 2 - Preview |
| Page 3 - Delivery / Specs |
| Page 4 - A Look Inside |
| Page 5 - Result Analysis and Discussion |
| Page 6 - Conclusion |
A Look Inside
The first hint, that this is a high-quality power supply comes when looking at the casing. The enclosure features an elegant design and a very solid lacker. The chrome face-plate at the top is a subject to personal taste. We would have loved to find differently colored, exchangeable fan grills in the delivery in order to make the unit blend in perfectly also in modded systems. Removing the lid reveals a fan from Hong Hua, which comes with an FDB bearing (fluid dynamic bearing), which does a great job, keeping the unit cool at very low noise.
Right behind the AC receptable there starts the input filtering stage. There is a separate PCB, where two Y and one X capacitor can be found. Going on step further to the main PCB there are two coils, one X and four Y caps as well as surge protection. Now four 5R199P power transistors from Infineon follow, which have been mounted on a thick aluminum profile receiving efficient cooling. Meanwhile we’re where power factor correction is happening and for that purpose there is one SCS110AG Schottky diode, two 6R099 MOSFETs and two big APFC bulk capacitors. Combined they’re offering 1100uF capacitance, while there are two different ones being used. The bigger one features 650uF at 400v and the smaller one is good for 450uF at 400V. If we now were to have a close look at the voltage regulation stage we’d have to disassemble the unit completely, which means unsoldering components from the main PCB. Since we do not do that, we cannot tell you what components have been used here, but we will make an educated guess at a later stage. Let’s jump to a small daughter board, which features all the protection mechanisms, of which a WT7527 chip is taking care. In this area of the PSU, after the voltages haven been regulated to 12V, 5V and 3.3V, there are electrolyte capacitors from Nichicon. Continuing to the PWM controller we find a CM6901, which is usually combined with a CM6502 regarding the PFC. Last but not least, we’re having a look at the large daughter board, that has been equipped with the different connectors for the modular cables. As we can see here all the soldering points have been equipped with connectors, which is the case with all the Seasonic Prime series power supply that have more than 850 Watt output power. Checking the capacitors, we see a mixture of ones from Nichicon and Chemi-Con.
| Page 1 - Introduction |
| Page 2 - Preview |
| Page 3 - Delivery / Specs |
| Page 4 - A Look Inside |
| Page 5 - Result Analysis and Discussion |
| Page 6 - Conclusion |
Result Analysis and Discussion
Efficiency |
|||
| Load | Pin(W) | Pout(W) | Efficiency |
| 10 % | 94.25 | 86.88 | 92.18 % |
| 20 % | 183.99 | 173.77 | 94.44 % |
| 50 % | 461.50 | 436.92 | 94.67 % |
| 100 % | 944.10 | 877.54 | 92.95 % |
The 80Plus Titanium certification requirements (90% - 92% - 94% - 90%) are surpassed especially at 20% Load. The full Load efficiency is a bit higher at 230V AC. This is the case with most of todays PSU's an it mainly originates from the reason of lower losses in the AC filtering stage and the PFC at 230V AC. The 230V AC 100% Load efficiency is 90.68%.
Output Stability |
|||
| Load | Rail | Loading(A) | Output(V) |
| 10 % | 3.3V | 1.07 | 3.37 |
| 5V | 1.07 | 5.03 | |
| 12V | 6.23 | 12.23 | |
| 20 % | 3.3V | 2.14 | 3.37 |
| 5V | 2.13 | 5.02 | |
| 12V | 12.44 | 12.26 | |
| 50 % | 3.3V | 5.34 | 3.36 |
| 5V | 5.30 | 5.02 | |
| 12V | 31.14 | 12.34 | |
| 100 % | 3.3V | 10.59 | 3.34 |
| 5V | 10.59 | 5.00 | |
| 12V | 62.1 | 12.44 | |
The Voltage Regulation of this PSU is very good. It makes use of a DC-DC topology. This means, that the Seasonic Prime Titantium 850W is mainly a 12V PSU and then generates its 5 and 3.3V from 12V. This is a modern approach, and since the Load is mainly on 12V it makes a lot of sense. For almost any PSU which makes use of this topology crossload tests do not present a problem.
| Noise | |
| Load | |
| 10 % | Noiseless |
| 20 % | Noiseless |
| 50 % | Noiseless |
| 100 % | silent |
If we listen closer with the power supply, there is no noise until 50%. The Seasonic Prime Titantium 850W is a semi passive power supply and the fan kicks in, when 50 percent load is being surpassed. Even at 100% load the unit can still be described as silent.
| Page 1 - Introduction |
| Page 2 - Preview |
| Page 3 - Delivery / Specs |
| Page 4 - A Look Inside |
| Page 5 - Result Analysis and Discussion |
| Page 6 - Conclusion |
Conclusion
With the Prime Titanium 850W Seasonic released an absolute high-end power supply. There is a costly AC filtering stage, an extremely high end fan, and the massive use of Japanese capacitors, which - amongst other parts - add up to a great product. All the components mentioned comply with highest standards and its hard to find other PC PSU's which are built according to similar guidelines. Furthermore this PSU is very reliable even if you plan with it for long term usage. Overall there is simply nothing to complain about this unit and judging by the 10 year warranty plan you get with these units, the vendor is also highly confident that this is a solid product. Should such a unit ever break down, then you'll receive a brand now model at that point in time. As we already mentioned, the only thing we'd like to see are exchangable cover plates in different colors. Would there be such cover plates, then unit would blend in absolutely perfect in any high-end modding build as well.
This high-end power supply is absolutely worthy of receiving five out of five stars.
| Page 1 - Introduction |
| Page 2 - Preview |
| Page 3 - Delivery / Specs |
| Page 4 - A Look Inside |
| Page 5 - Result Analysis and Discussion |
| Page 6 - Conclusion |